Improvement in dovetailing-machines



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N- PETERS, PEOTO-LITHOGRAFHER, WASHINGYON. D (IV I daitrd time @anni mijn.

Letters Patent No. 110,642, dated January 3,1871.

IMPRQVEWIENT IN DOVETAILING-MACHINES.

The Schedule referred to these Letters Patent and making part o1' the name.

To aZLwhonLit may concern Beit known that I, Hanny H. Evanrs, of the city of Chicago, in the county of Cook and State of Illinois, have invented a certain new'and useful Improvemcutin'Dovetaillng-Wachiues, of which the following is a specification.

Nature of the Invent/ion.

In general principle this invention is similar to that patented by me June 7, 1870. It consists in an improved construction and arrangement ot' the parts as hereinafter described.'

General Description.

In tho drawing- ITigure 1 is a plan 5 Figure 2; a side elevation 5 Figure 3, an-end elevation 5 Y Figures't, 5 and 6, 7 and 8, detail views.

A represents the frame, which may be of any convenient form to sustain the parts.

Bis the driving-shaft, operated by pulley a.

At itsopposite end is a pulley, b, having a band, c, which passes over pulley d at the top, thence down around and over the pulleys f g, which give motion to the tools. j Pulley d is adjusted higher or lower to tighten the band by means of a hand screw, I1., and pulleys fg` are mounted in a rocking .mandrel-'trarne O, turning on.tlie axis e, tig. 3, by which means the band always keeps 'equal tension, whatever the position of the pulley may be The rocking mandrel-frame C rests in' a carriage D, which is thrown up and down vertically by means of a lever, E, and pitman It.

The spindle G of this carriage rests in a pivoted box or bearing, H, at the bottom, which thus forms 'a guide.

On the top of this is cut a screw-thread, on which rest-s andadjusts a nut, t, that forms a stop to the fall of the spindle. The object of this is to adjust the spindle to the proper height to' allow the tool to cut at the proper altitude in horizontal work. Instead of this arrangement the uut may screw upon the spindle itself, andthe top of thc box form the stop.

rlhe carriage D has'a stilif tongue or bar, l, fig. 3, projecting under the front end of the mandrel-framc 0. A screw, m, passing through this tongue, and another, n, passing through the frame, enables the said frame to beladjustcd higher or lower, to adjust the tools and reta-in them. in 'a fixed position, as will presently be described.

The carriage has `also an arm, 0,011 one side, which slides in a way, 1)formed by two upright bars, :v x', to keep it in place, and a gibbox, q,'on the other end, which slides on lever vI.

The lever is also movable up and down by means v of a screw, t. When this lever is set vertically, the

tool cuts the vertical sides of theY dovetails, and when set angularly it cuts the angular sidesot' the pins.

An elbow, K, iig. 6, is pivotcd at j on the inner side. of the spindle. Its lower end rests between screws u lu, by which 'means its upper end is adjusted higher or lower. lhis elbow acts in conjunction with a pivoted stop, L, ou the frame above, to gauge the height to which the carriage rises.

This stop-arrangement is intended for use only in cutting those dovetails or pins that are not cut entirely through the lumber, better known 'as blind dovetails. In through-work there is no gauge to the upward or downward cut.

To allow the angular action of the carriage the box H has a pivot-jointv at c, which admits the proper rocking motion. l The table M,upou which the lnmber-1ests moves transversely upon `ways w w, iig. 1. It has upon its under side a rack, N, which receives motion through a train of gears, l 2 3, as clearly shown in gsA and 5.

These gears are mounted upon a bearing, p', ex, tending horizont-ally from the frame, and made acljustableverticall y by means of slots q g1' andscrews 1*"1", to keep the wheels in gear, and compensate for Wear. 'For the same purpose the gear 1 is mounted upon one end of a bent lever s,'which turns upon the spindle t -as a fulcrum, and has a rubber or equivalent spring, o',pressing against its opposite arm, thus insuring the connection between gear l and the rackN.

A shaft, O, extends across on one side ot' gear 3, having a det-eut, x,`whi ch strikes into the teeth and holds the gear stationary in any desired position.

Au arm, y, of this shaft, with weight z, holds the detent in connection with the gear, except when it is thrown out by elbow a', for thc purpose of allowing the gears to act.

Gear 3 is operated by adouble-actiug pa-wl, P, piv-l ot'edjto swinging lever Q, which-has its bearing upon the axis of the gear.

The outer end of the pawl-shauk is made changeable upon a gauge-head, b', of the lever, so that, as it is changed from one position to the other, the pawlpoints c c' will be .correspondingly changed or adjusted to engage with the teeth ofthe gear, and correspondingly move it backward or forward, consequently moving the table in the same manner. In this mauner dovetails may beformed moving in either 'direction.

The lever Q, with pawl P, rests over a gauge-segment, It, having marked thereon a scale in inches vand' subdivisions, and also an adjustable stop, Sfoyl which means the movement of the table may be adjusted exactly. to the dovetail which is to be made.

"As the lever and pawl swing from one side to the other, the dovetails will be formed at given distances apart, which distances will be increased or lessened according as the lever and pawl have a long ora short stroke, which is governed by the stop S. The motion of the lever, therefore, is simply to feed the material along. A

There the. dovetail-pins are to be ont through several thicknesses of board at one operation, in order to preserve the same angle in each, Iemploy a gangeblock, T, on top the table, which is so jointed or connected therewith as to be capableof changing to any desired lateral angle This is done by means of a lever, Urwhich rests in a gnide-gange,V, above.

The angle to whichthis block is set must correspond with that of the lever or WayI, which governs the motion of the carriage, and the pieces will rest against the side of the same. In this manner the dovetailpins may be formed in series in a perfect and rapid manner.

A movable stop, X, :is connected with and slides on the gauge-block T, for gauging the lengt-b of thestnii. This stop is fastened to the gauge-block -at any de-` sired point by hand-screw s1.

This gauge-block T has a central bearing, f', which restsin a way, g', of the table, and, if desired, the

ends may be arra'uged in the same manner, the object' of which is to renderthc block adjustable laterally on the table.

The to'ols 71.' i may be of any kind suitable to the Work. The double tools represented are for the purposeof cutting the dovetail tenons, one cutting above andthe otherbelow, and the work moving horizontally, For this use the vertical adjustment of the mandrelframe C, before described, is essental to bring the line of cut nearer together or farther apart, thereby producing the tenons of different sizes or thicknesses. I combine with either or both tools a small circular saw or cutter, Y, which encircles the tool and cut-s or trims the ends ofthe boards. .It is connected byarms ldlc with a collar, m', which is in the form of a nut, and screws upon the shank or end of the tool-holder or mandrel. Its construction is such that it does not interfere with the action of' th'e tool,.and'it is easily removed from place. l

Back of this nut mi, and on the shank or mandrel, I place a screw-collar, fm?, which serves the purpose of a loclc-nut to retain the saw Y xcdly in place in any desired position.

Claims.

That I claim, and desire to secure by Letters Iatent is 1. The lever slide I, withv its pivoted gib-box q', the arm O 'with its guide-bars x' x', the spindle Gr with its pivoted guide-box'H, combined with the carriage D and mandrel-frame O, for the purpose of governing the direction of the movements of said carriage I) and mandrel-frame O, substantially as' shown and described.

2. The pivoted box H and adjusting 4nut t', when i n combined with thespindle G, provided with pin 7c, arranged as described, and operating in the manner` and for the purpose specified.

3. The combination, with the stop-arrangement H 'i k and spindle G, of the adjustable elbow K and stop L, arranged as described, and operating in thc man Iner and for the purpose specified.

4. The combination, with the vertically-moving carriage D, of the rocking mandrel-frame C carryingt the tools h t', and made adjustable by means ot' screws m 1:. inthe manner and for the purpose specied.

5. The lever Q, double-acting pawl P, gauge-seg ment R, stop S, rubber spring t" and bearing ll 4for insuring the conncctionof the gears and oompcnsat ing4 fol-wear, when combined with vthe gears 1 2 3 and rack N, for giving motion to and adj nstiugthe action of the table, substantially as described.

6. The weighted shaft O,- with detent x, combined with the gear 3, and the lever and pawl Q P, as described.

7. The angularly-adjustable gauge-block T and stop X, in combination with the table-Mfin the manner and for the purpose specified.

In witness whereof I have hereunto `set my hand this 20th day of September, 1870. 'l

HARRY H.A EVARTS.

Witnesses:

VJosHUA GAsKILL,

WASHINGTON H. Ransom. 

